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How to set-vcpu 8 threads - 1 each from 8 cores

5bf5edcf-0c6b-48bc-b784-8c42916fe392Jan 15 2019 — edited Jan 17 2019

Hi, we are licensed for 8 "Solaris CPUs" and we have a whole SPARC T8-1 to run on. T8-1 has one socket, 32 cores and 8 threads per core i.e. in Solaris terms that's 256 CPUs.

If I do >ldm set-vcpu 8 mydomain

then I am pretty sure it will allocate the first 8 threads, which are all on the same core.

However, if there were a way to allocate 1 thread off each of the first 8 cores, then my app might run faster?

So I'm thinking, what about this:

>ldm set-vcpu 1 mydomain

>ldm set-vcpu 7 unuseddomain

>ldm add-vcpu 1 mydomain

>ldm add-vcpu 7 unuseddomain

>ldm add-vcpu 1 mydomain

>ldm add-vcpu 7 unuseddomain

>ldm add-vcpu 1 mydomain

>ldm add-vcpu 7 unuseddomain

>ldm add-vcpu 1 mydomain

>ldm add-vcpu 7 unuseddomain

>ldm add-vcpu 1 mydomain

>ldm add-vcpu 7 unuseddomain

>ldm add-vcpu 1 mydomain

>ldm add-vcpu 7 unuseddomain

>ldm add-vcpu 1 mydomain

>ldm add-vcpu 7 unuseddomain

a) Will that get mydomain 8 threads, each one from a separate core?

b) Does that have the potential to run faster than 8 threads from a single core?

c) Can I/should I follow it up with >ldm set-mau 8 mydomain ?

Thanks, Jim

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Added on Jan 15 2019
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